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41.
Two of the most common cytogenetic changes in therapy- and chemical- related leukemia are the loss and long (q) arm deletion of chromosomes 5 and 7. The detection of these aberrations in lymphocytes of individuals exposed to potential leukemogens may serve as useful biomarkers of increased leukemia risk. We have used a novel fluorescence in situ hybridization (FISH) procedure to determine if specific aberrations in chromosomes 1, 5 and 7 occur at an elevated rate in the blood cells of workers exposed to benzene. Forty-three healthy workers exposed to a wide range of benzene concentrations (median 31 p.p.m., 8 h time-weighted average) and 44 unexposed controls from Shanghai were studied. Whole blood was cultured and metaphase spreads were harvested at 72 h. Benzene exposure was associated with increases in the rates of monosomy 5 and 7 but not monosomy 1 (P < 0.001, P < 0.0001 and P = 0.94, respectively) and with increases in trisomy and tetrasomy frequencies of all three chromosomes. Long arm deletion of chromosomes 5 and 7 was increased in a dose-dependent fashion (P = 0.014 and P < 0.0001) up to 3.5-fold in the exposed workers. These results demonstrate that leukemia-specific changes in chromosomes 5 and 7 can be detected by FISH in the peripheral blood of otherwise healthy benzene-exposed workers. We suggest that aberrations in chromosomes 5 and 7 may be useful biomarkers of early biological effect for benzene exposure.   相似文献   
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BACKGROUND: Mycobacterial infections are extremely complex diseases, either due to the various clinical manifestations, or to the various involved kind of mycobacteria, or to the different sensibility to antibiotics. The authors review retrospectively their series, evaluating the management of pediatric cervical lymphadenitis due to mycobacterical etiology. METHODS: From 1975 to 1998, at the Department of Pediatric Surgery of the university of Siena, 88 children were evaluated for laterocervical lymphadenopathy. Among these, 29 children, aged from 14 months to 13 years, were diagnosed as affected with lymphoadenopathy due to mycobacteria. Therapy of choice was the association of surgery and antibiotics. This behaviour allowed us to approach both advanced lesions, in active colliquation, and progressive ones. RESULTS: Results were unquestionably positive, with a complete resolution and good esthetical results in 93.2% of cases. In 6.8% of cases there was a recurrence, which required reintervention. CONCLUSIONS: On the basis of our series, we agree with the international literature in affirming that, in cases of mycobacterial lymphadenopathy, a combined antibiotic and surgical therapy is necessary. However, controversy about such a complex and difficult pathology is opened and unsolved.  相似文献   
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The role of soy products in reducing risk of cancer.   总被引:14,自引:0,他引:14  
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Background and AimsTo determine whether and to what degree exposure to isoflavone-containing soy products affects EF. Endothelial dysfunction has been identified as an independent coronary heart disease risk factor and a strong predictor of long-term cardiovascular morbidity and mortality. Data on the effects of exposure to isoflavone-containing soy products on EF are conflicting.Methods and ResultsA comprehensive literature search was conducted using the PUBMED database (National Library of Medicine, Bethesda, MD) inclusively through August 21, 2009 on RCTs using the keywords: soy, isoflavone, phytoestrogen, EF, flow mediated vasodilation, and FMD. A Bayesian meta-analysis was conducted to provide a comprehensive account of the effect of isoflavone-containing soy products on EF, as measured by FMD. A total of 17 RCTs were selected as having sufficient data for study inclusion. The overall mean absolute change in FMD (95% Bayesian CI) for isoflavone-containing soy product interventions was 1.15% (?0.52, 2.75). When the effects of separate interventions were considered, the treatment effect for isolated isoflavones was 1.98% (0.07, 3.97) compared to 0.72% (?1.39, 2.90) for isoflavone-containing soy protein. The models were not improved when considering study-specific effects such as cuff measurement location, prescribed dietary modification, and impaired baseline FMD.ConclusionsCumulative evidence from the RCTs included in this meta-analysis indicates that exposure to soy isoflavones can modestly, but significantly, improve EF as measured by FMD. Therefore, exposure to isoflavone supplements may beneficially influence vascular health.  相似文献   
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The aim of this research is to evaluate in vivo the characteristics of microcirculation after taking a biopsy sample from the oral mucosa. 20 patients were recruited to the study and all underwent an oral mucosa biopsy for the excision of benign neoformations. The modifications in the oral microcirculation were evaluated in vivo in correspondence to the surgical site through videocapillaroscopy at three different times: 30 min before the biopsy; 48 h after the biopsy; and 7 days after the biopsy. The statistical significance was checked with the Mann–Whitney U-test (P < 0.05). The analysis of videocapillaroscopic patterns showed statistically significant variations relative to the capillary loop density; the diameter of the outgoing loop; and the length of the capillary loop. In conclusion, the study describes a simple and reproducible model for the study of wound healing from a microcirculatory point of view.  相似文献   
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Miniaturization of analytical procedures has a significant impact on diagnostic testing since it provides several advantages such as: reduced sample and reagent consumption, shorter analysis time and less sample handling. Lab-on-a-chip (LoC), usually silicon, glass, or silicon-glass, or polymer disposable cartridges, which are produced using techniques inherited from the microelectronics industry, could perform and integrate the operations needed to carry out biochemical analysis through the mechanical realization of a dedicated instrument.Analytical devices based on miniaturized platforms like LoC may provide an important contribution to the diagnosis of high prevalence and rare diseases. In this paper we review some of the uses of Lab-on-a-chip in the clinical diagnostics of immune-mediated diseases and we provide an overview of how specific applications of these technologies could improve and simplify several complex diagnostic procedures.  相似文献   
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